what are the negative driving dynamic effects of negative camber?

[twobone]

To fit 225/45/16s up front on my 911SC, it has been suggested that I run some negative camber.

Why is that a bad thing? What does that do to the driving dynamics?

Does it significant impact tire life?

I have stock suspension and I'm having the car lowered to Euro specs


Mike

[pwd72s]

Too much negative camber will assure that your tires will wear prematurely on the inside. The plus side is that you will have more grip in the twisties, and more fender clearance. It's all a trade-off thing.

[MY83SC]

Exactly. Take a look at the thread that North Coast Cab wrote. Shows a track tire that appears to have a bunch of negetive camber and the affect of it.

[MY83SC]

I sometimes wonder. People, like Jack, who often track their car but also drive it on the street on a daily basis. Do they change the camber between races and street use? Or just live with the added wear?

[Eric Coffey]

I think that the wear issue isn't really a concern with modest neg camber settings. You can probably run up to -1.2-ish without any significant uneven wear (depending on your driving style/habits). Besides the wear you might notice the front tend to wonder a bit or become a little "darty", especially on uneven road surfaces or in windy conditions.

[Formerly Steve Wilkinson]

What does it wonder? Which way to turn?

Stephan

[pwd72s]

Originally posted by Eric Coffey
I think that the wear issue isn't really a concern with modest neg camber settings. You can probably run up to -1.2-ish without any significant uneven wear (depending on your driving style/habits). Besides the wear you might notice the front tend to wonder a bit or become a little "darty", especially on uneven road surfaces or in windy conditions.

My rears are at approx. 1.4...being more concerned with the bite out of the turns. Yup! It's all compromise..

[Jeff Alton]

I run 1.5 on the front and 2.0 on the rear. If you can not get enough caster in the front wheels the car will tend to hunt around a little. I have no uneven wear on the front, but I sure do on the rear!!

Jeff

[Eric Coffey]

Originally posted by Formerly Steve Wilkinson
What does it wonder? Which way to turn?

Stephan

Ha, good catch. Obviously, meant to type "wander".

Weeeee-ouuuu, Weeee-ouuuu, Weeee-ouuuu.........
"Warning, spelling police".....

Oh, and yeah, a good compromise would be somewhere around
-1.8 rear, -1.1 front, with max caster.

[Jack Olsen]

Originally posted by MY83SC
I sometimes wonder. People, like Jack, who often track their car but also drive it on the street on a daily basis. Do they change the camber between races and street use? Or just live with the added wear?

I run -2.2F, -3.2R, or thereabouts. Since I use the same tires on street and track, the inside edge wear (from regular driving) balances out the outside shoulder wear (from track driving).

The only things I change for the track are the rear wing and the brake pads.

[dd74]

Tyson told me I'm running something like -3.4. And that the toe-in might also have to do with a lack of premature wear.

[stuartj]

Originally posted by pwd72s
Too much negative camber will assure that your tires will wear prematurely on the inside. The plus side is that you will have more grip in the twisties, and more fender clearance. It's all a trade-off thing.

Dont forget you are reducing contact patch in a straight line, and under "dive" where the front is loaded up, the more the neg, the less contact patch available for braking. As you say, a trade off.

stuart 86 carrera

[stlrj]

Steering effort increases with negative camber.

Joe
86 Carrera

[Wil Ferch]

To summarize two important points made here...but for emphasis...lots of neg camber will wear inside edges ( especially if there you don't do a lot of track days) and the straight line braking may be materially compromised because you end up with a bicycle tire contact patch in the straight-ahead position.
Some personal experience...I was running ( unknowingly) much more neg camber in the RF than I did LF... and the resulting "minor" squirreliness was driving me crazy. Couldn't even describe it properly as it was "OK" most of the time...but had an unsettling feeling. Once they were trued up to match...the car was transformed... very very noticable improvement.
--Wil

[ted]

If you are getting uneven tire wear you can always swap tires side to side. Your left inner becomes your right outer and the tire direction remains the same.

Good points on all of the above, negative camber is a good thing.
Imagine under hard cornering how the contact patch of a front tire with very little camber looks, missing a lot where the rubber meets the road.
Suddenly your 225 under cornering has the contact patch of a 185.